Retort



K. L. FORD July 26, i927.

RETORT 3 Sheets-Sheet l Filed March l2, 1926 v1,636 768 July 26, 192 7. K L FORD RETORT Filed Maron 12, 192e z sheets-'sheet 2 o n Q u E QM i l Illill lllllllm .Il |W-|U ,iik WM. x* NW \\M. IIII |NWlINHIWWiIILIIWIIMJMWNI V HIlWWHHHUIFUIHHHWHUIIIHIIHHm f ma mh En m Patented July 26, 1927.

iii 1,636,166`

UNITED STATES-:PATENT g.oF-Fica.

KARL L. FORD, OF EAST ORANGE, NEWiJERSEY, ASSIGNOR T0 GLASS CONTAINEBIAS- SOCIATION OF AMERICA, OF NEW YORK,`N. 'Y., A CORPORATION OF DELAWARE.

' BET/oms.

Application led March 12, 1926. Serial No. 94,128.

' This invention relates to retorts andpary ticularly to the type of retort which may be used for sterlization of Lpreserved products packed in glass or other containersfl The main object of this invention is to provide an apparatus of the type indicated which is economical, rapid and dependable in its operation.

Further and more specific objects, features and advantages will more clearly a pear from the detailed description given elow taken in connection with the accompanying drawings which form a part of this specification.

In the drawings, Fig. 1 is a vertical elevational view of one form of apparatus embodying the invention as applied to a vertical retort. l.

Fig. 2 is a similar view, but showing a modified arrangement of the apparatus.

Fig. 3 is a side elevational view showing apparatus embodying the invention as applied to a horizontal retort or vessel. l v In Fig. 1 a vertical retort'vessel 10is indicated which may comprise a cylinder for receiving the containers of preserved prod` ucts which are to be sterilized or otherwise treated. The containers which may be of glass, tin or the like, in whichl preserved food or other material is packed, may be introduced into the cylinder 10 through an 'opening at 11. This opening may be covered by a cover plate 12 designed to be clamped in sealed posi-tion by suitable clamping devices 13. l

Steam or other heating medium, preferably a vaporized heating fluid, may be introduced through a conduit 14 from a source of supply 15. With the apparatus as shown in Fig. 1 the steam is uniformily,distributed within the bottom portion of the retort by means of a perforated header 16. yAt the top of the retort a plurality of exhaust passages as at 17 are communicative with an exhaust conduit 18 which extends down to the conduit 14. At the junction of the conduits 18 and 14 a suitable aspirator 19 is installed.v This aspirator may comprise a steam nozzle 21 directed toward the intake conduit, and positioned within a housing member 20, the annular space between the nozzle and housing providing an yarea for receivingthe mixture yexhausted from the retort through the conduit 18.

1t will be noted kthatthe exhaust openings 17y abover referred to are positioned around the periphery of the retort just `beneath the covervk 12 and therefore the cover may be freely removed or replaced without interference with these openings andthe conduit 18. However, in certain instances it may be desirable to provide a header as at 22 having a largeL number of spaced openings asydoes the header 16. This header 22 may be supportedI by and made communicative with a conduit 23 which in turn may be connected up, with the aspirator 19 alternatively or simultaneously with the conduit 18. These alternativelexhaust facilities ma be both provided upon the same retort if e'sired, for flexibility of operation as hereinafter further explained.

In the cover 12 a gas release cock 24 may beprovided. Also, if desired, a manually releasable spring valve 25' may be provided for use in releasin air while the operation ofthe retort is being initiated or at other times kA suitable automatic safety valve for the retort may be provided at 26 for relieving excess pressures. i

At the bottom of the retorta valve 27 may be provided as a condensate drain. source of cooling water 28 may be made communicative with the header 16 through the intake pipe 14. Cold water may thereby be introduced to rapidly cool the retort after each operation. v

In order under certain conditions to maintain desirable pressures within the retort independently of the temperatures, a source of compressed air may be provided as at 29 which is controlled b an automatic vvalve 30 as hereinafter-exp ained'in further detail. The compressed air is first admitted to a warming cylinder 31 which surrounds the conduit 18 whereby the air is preheated yand then introduced intofthe intake conduit 14 through a pipe connection 32. For reasons hereinafter described the connection 32 is preferably made smaller than the intake to the warming cylinder 31. i

`In order to provide a normally constant Aor other predetermined temperature control withiny kthe retort, suitable thermostatic means of any well known construction such as an automaticvalve 37 maybe actuated by a temperature sensitive bulb located vin a pocket 33 which is in communication with tive bulb a suitable conduit 36 extends to thexV automatic'valve at 37 arranged in the steam supply pipe and actuated by pressure changes in lthe sensitive bulb. This control valve .and associated parts comprise thermostatic means for controlling or limiting the steam vflow yand consequently serve to control or limit to a predetermined value the temperatures within the retort.

For independently and automatically controlling orlimiting to 'a predetermined value the retort pressures, the valve 3() above referred to is provided'in the air supply conduit 29. -Any suitable and well known automatic` pressure operated valve control meansmay be provided at 38 and made communicative with the warming cylinder' 31vthrough a conduit 39. A pressure gauge 40 is provided vfor visually indicating the p-revailing pressures within the warming cylinder 31. As above stated, the conduit 32 is preferably made somewhat smaller than the intake to the warming cylinder 31. JAccordingly, during periods of rising pressure within the retort, the pressure within they warming cylinder will be built up faster than in the chamber of the retort. Hence,

u as the air inlet conduit 39 for the automatic air valve 1s subjected to the pressure 1n the warming cylinder, the air control valve will be closed by this increased pressure operating through pipe 39 before the retortI pressure has increased beyond the desired operating pressure. Accordingly this arrangement prevents excessive fiuctuations of the retort pressure.

`In yoperating the apparatus above described, the retort is first loaded with the sealed containers of food products and the cover 12 is firmly sealed in place. The condensate drain 2,7 is opened slightly as is also the pet cock 34 at the pocket 33. Steam is thereupon admitted from the source of supply 15 and passes through the control valve 37, through the aspirator 19 and conduit 14 and is admitted to the retort through the header 16. Thestea'm thereupon strikes the cold Icontainers and retort walls and is more or less condensed. The condensate drains to the bottom of therretort and may be dischargedthrough the valve 27, kept slightly open or cracked. During the initial stages of the operation, the condensation of the steam makes possible a free flow through the aspirator without building up a back pressure in the retort. The exhaust conduit 18 will then begin to receive through the openings 17 the entrapped air from the top of the retort. The suction created by the flow of steam through the aspirator will withdraw this air, and later an air and steam mixture, from the upper portion of the retort, and force it backl into theretort through `the steam inlet. This operation of the aspirator will result in a thorough and rapid circulation through the retort and cause the air therein to be thoroughly and uniformly intermixed with, and heated by, the steam. As a result the retort may be very rapidly and uniformly brought to the desired operating temperature. In apparatus of this type the condensed'steam within the retort will gather upon the containers therevin resul-ting in a water lilm thereon. Heretofore such water film hasinterfered with the rapid heating of the containers. However, with the presentinvention the rapid lcirculation ofthe gases or'ot-herrheating medium through the retort will tend to minimize this water film and thereby make possible a more direct and prompt application of heat to the containers and the products therein. i The rate of heating will be further increased by reason Yof the relatively high velocity of flow of vapors past the containers. Y

According toformer methods of retort voperation the steam is ladmitted at thel bottom of the retort and `there is rapidly condensed. The rapid condensation of the steam and consequent reductionv of its effective pressure prevents such steam from rising andintermixing with the entrapped air at the top of the retort. Accordingly, with such apparatus it has heretofore been the practice to provide a large vent or open valve permitting the free escape of the airV and also volumes of mixed air and steam at the top.

This of course not only involves a waste of steam but also a waste of power in the form of compressed air. In operating the above described apparatus comprising this invention, the rapid circulation'of the steam and air within the retort enables the steam to become rapidly and uniformly distributed throughout the retort load. This will result Vnot only from the admixture of the air and steam within the retort, but also because of the thorough mixing action which will take placey at the aspirator. At the same time undesired venting and waste'of steam and air may be eliminated.

As the average temperature of'theretort increases, the back pressure will increase and the exhausting action of the aspirator will decrease. However, the necessity for circulation occurs principally duringthe early v stages of thel operation and it is during such period that the steam flow through the aspirator is greatest, producing the desired rapid exhausting action ony the upper part of the retort. After the desired normal operating temperature of the retort is reached,

tf1-,esencia the ythermostatically Aoperated,` automatic valve 37 willrestrict or closelofffthesource of steam supply 15 and the retort temperat'ure'may thusbe controlled-g If no coinpressed ai'r is available ori-i'frforr'other reasons itis desired tooperate theretortfmere- Vly from-a source of steam supply',l the pressure within the' retort may be controlled by -opening the valve 24l Vto'` release a small greater than one-half pound above the pressure of clear steam for the particular operating temperature, then the valve 24 may be merely closed or cracked.

It is desirable, however, in most instances to use the air supply above referred to. With an air and steam mixture, it is usually necessary to maintain within the retort a pressure above the steam pressure normally required to maintain the desired' temperature. Accordingly, the automatic air control valve 30 is adjusted to admit air under pressure until such time as the desired working pressure within the retort is reached. The automatic air valve thereafter serves to control and maintain the retort pressures at the desired predetermined value. The warming cylinder 31 serves to prelieat the air prior to its admission into the retort and therefore uniformity of heating throughout the retort is not interfered with. As above stated the warming cylinder 31 serves the further purpose of providing a desirable source of pressure for control of the automatic pressure valve. If the retort pressure should rise above the predetermined desirable value, the relief valve 26 will4 open. The relief valve may be either automatic in its operation or if desired other well known forms may be used.

The air inlet valve and relief valve may be, if desired, air operated by the same control instrument actuated by the retort pressure and capable of adjustment for any operating pressure in the conventional manner as will be further referred to in connection with Fig. 3.

If desired the retort may be water operated, that is, the sterilization or other operations may be carried out with the retort chamber filled with water above the upper level of the containers therein. During such operation the exhaust openings at the upper portion of the retort should be located beneath the water level and then the action of the aspirator will correspond to its action with steam, except that water will be circulated instead of steam and air. In thus processing products packed in glass y containers, a substantial pressure is required to hold down the container covers in the retort.l

Such pressure-may -befreadily maintained by jiadmitting compressed air in the. same. man- .ner as -described -iir connection with the air andsteam method of operation. yWith the .i waterI operation the drain E27 iat'. the bottom `of the? retort is not opened f until the retort is to be opened. Y Y* AActual tests ofthe above vdescribed 'apparatus -with thermocouples arranged 'in variousf partsbof,A the retort indicate a -substan- A' :tia-l, 1 uniformity -of heating throughout the retortfand shoiv a-marked increase in Vtlie lrate 'of :heating vover ftliata obtainable without the circulating means l embodying -this invention.

In Fig. 2 similar apparatus is illustrated in which steam is admitted at the top of the container while the air and steam mixtures are withdrawn from the bottom portion of the container. With suchy apparatus the condensation from the steam will vrun down over the containers in the same direction of How as does the circulating steam and air. Accordingly the heat of the condensate will materially supplement that of the steam in rapidly heating the lower portion of the retort and also the circulation of the steam assisted by gravity will cause the film of condensate on the containers to be rapidly carried awa-y or substantially minimized. Corresponding parts in Figs. l and 2 bear the same reference characters and accordingly a specific detailed description of theapparatus in Fig. 2 is unnecessary.

Vhile Figs. 1 and 2 illustrate the invention as applied to a vertical retort the same invention may of course be used in connection with the horizontal form of retort illustrated in Fig. 3. In Fig. 3 parts'corresponding to those of Fig. 1 likewisebear the same reference characters with the exception that in Fig. 3 elongated intake and exhaust headers 41 and 42 respectively are provided extendingr substantially the entire length of the retort. Also as indicated at 43, a suitable steam trap of any well known construction may be provided for draining away the condensate, and may be used alternatively with the valve 27.

As above stated kthe air relief valve together with the air inlet valve may be, if desired, operated by the same air control instrument actuated by the retort pressure. Such an arrangement is indicated in Fig. 3 where 26 comprises a pressure controlled automatic release valve actuated through an air tube 39` which tube may be communicative with the air inlet valve control conduit 39.

While I have described my improvements in great detail and withrespect to certain preferred forms thereof, I do not desire to be limited to such forms or details since many changes and modifications may be,

made and the improvements embodied in widely different forms Without departing from the spirit and scope of the invention in its broader aspects.

pended claim'.

What I claim as new and desire to secure by Letters Patent is:

Apparatus of the class described comrising` a elosedvessel, an intake conduit or admitting a vaporized heating medium into. the vessel, an exhaust conduit for the vessel communicative therewith at a plu- Henoe, I desire to cover all modifications and forms `coming within the language -or scope of the ap- Losanna rality of points spacedffrom theregion of 15 whereby the gaseous contentsV of. the vessel 20 are exhausted therefrom and returned there'- to intermixed With said heatingmedium to provide approximately uniform heating throughout the vessel.

In testimony' whereof I have signed-'my 25 name to this specification.

KARL L. Folin?, 

